Electrical distributor



July 10, 1923.

W. B. STEARNS ELECTRICAL DISTRIBUTOR Filed April 25. 1922 Patented Julyl0, 1923.

WILLIAM B. STEARNS, OF MILTON, MASSACHUSETTS.

ELECTRICAL DISTRIBUTOR.

Application filed April 25, 1922.

T 0 all whom t may concern Be it known that I, WILLIAM B. STnAnNs, acitizen of the United' States of America, and resident of Milton, in thecounty of Norfolk and State of Massachusetts, have invented new anduseful Improvements in Electrical Distributors, of which the fol" lowingis a specification.

This invention relates to electrical distributors of the type used tocontrol the ignition of internal combustion engines, commonly calledcommutatore or timers, but certain of the features of the invention arecapable of general application.

Most distributors or timers in common use have a spring-pressed contactarm arranged to follow a closed circular path and wipe across spacedcontacts in `the distributor housing. Such d'evices have several seriousdefects. The spring which forces the contact arm outwardly frequentlybecomes weakened or broken resulting in irregular operation or completefailure. Tear develops irregularties in the path followed by therotating arm such that the latter at times jumps over the contacts.Sparking between the contacts frequently occurs resultingr in 'burningand fouling of the contact members and sometimes in fires if gasoline orother highly inflammable vapors are present.

Objects of the invention are to provide a device of the class describedwhich will operate efficiently for an indefinite period withoutappreciable wear, to eliminate parts which may be easily weakened orbroken such as springs and other delicate parts. to prevent sparkingbetween the contacts and fouling thereof and in general to simplify andimprove devices of the character de scribed and to make them moreefficient and satisfactory in operation.

The invention comprises relatively mov able parts having opposed circuitclosing elements arranged to register with each other in successivepositions of the parts, at least one of the elements comprisingelectrical conducting Huid trapped in a recess.

For the purpose of illustration species Serial No. 556,391,

f the lgenus constituting the invention are shown in the accompanyingdrawings, in which:

` Fig. 1 is a side elevation with parts of the distributor in section;

Fig, Qv is a view similar to Fig. 1 showing 55 a. modification Fig'. 3is a section on the line 3-3 of Fig. 1.

The embodiment of the invention shown for the purpose of illustrationcomprises an electrical distributor or timer adapted for use incontrolling,- the ignition of an internal combustion engine. Theparticular type of commutator here shown is suitable for a four-cylinderengine. As shown, the distributor comprises a shaft l supported forrotation in bearings 5 on brackets 6 attached to any convenient portionof the engine frame. Any suitable means may be provided for rotating`shaft Il, such as a gear wheel or pulley 7 opera-ted by the enginethrough a suitable connection.

Surrounding shaft l (which is preferably of metal) and' fast thereon forrotation therewith, as by pins 8, is a` sleeve 9 of in- 75 sulatinp;material such as fibre or hard rubber which has a close sliding fit witha stationary casing 10 also of insulating material such as llibre orhard rubber. Upon one side of the casingv 10 are projections or S0bosses 11 upon which terminals 1Q are adapted to be made fast. Theelectrical contacts in the casing 10 to which terminals 1Q areVconnected are preferably formed by making' an opening 13 in each of thebosses 85 11 extending' from the exterior thereof to the opening; forthe rotor which comprises parts il and 9. Terminals 12 are fast inopenings 13 in any suitable manner as by the. screw threaded attachmentshown thereby closing; one end of each opening 13 which thereuponbecomes a recess opening; toward the rotor portion of the device.

The rotor portion of the distributor, comprising shaft 4 and sleeve 9,is provided 95 with recesses 14 spaced longitudinally andcircumfcrentially thereof. In the form shown each recess is at an angleof 90 to the next, and each recess 14 is in line with a correspondingrecess 13 in the stator casing 10, so that each quarter revolution vofshaft 4 will bring one of the recesses 14 into registration with one ofthe recesses 13. Recesses 13 and 14 are filled with a suitableelectrica] conducting Huid such as mercury. By reason of the close fitbetween the sleeve 9 and housing 10, the mercury in these recesses istrapped therein, and no loss or leakage thereof occurs.

In Fig. 2 a modified structure is shown, the general arrangement beingidentical with Fig. 1, but instead of having recesses in the rotorfilled with mercury metal plugs 14 are employed. As shown these plugsare round instead of oval, as are the openings 14 in Fig. 1., and theyhave a tight pressed lit in both shaft 4 and sleeve 9.

It will be understood that the shaft 4 constitutes the common return ofthe branched circuit and that this return may lead to ground or, byinsulating the shaft of the machine from ground, to the battery.

It will be clear from the above that the complicated mechanisms of thedistributors or timers in common use have been avoided and that goodcontact will be secured through the mercury contacts shown in Fig, 1 orthrough the metal and mercury contact-s shown in Fig. 2. The use ofmercury has the peculiar advantage that impurities and the scum producedby oxidation rise to the top of the pocket of mercury so that the metalis free from impurities as the parts of Contact in both of themodifications shown whereby a good electrical connection is consistentlyproduced. It will furthermore be evident that the sparking betweencontacts frequent in distributors of the ordinary type is entirelyavoided due to the close fit of sleeve 9 in housingl 10.

I claim:

1. An electrical distributor having relatively movable non-conductingparts in contact with each other, said parts having recesses adapted tobe brought into registration, and electrical conducting Huid in saidrecesses.

2.A An electrical distributor having relatively movable non-conductingparts in sliding contact with each other, circuit closing members onsaid parts arranged to register in certain positions thereof, thecircuit closing members on one part comprising electrical conductingluid trapped in recesses in said part by the sliding engagement of theparts.

3. An electrical distributor having a rotating part and a stationarypart in sliding contact therewith, one of said parts being formedv fromnon-conducting material, circuit closing members on both said partsarranged to register in certain positions, one of said memberscomprising electrical conducting fluid trapped in a recess in one ofsaid parts by their sliding contact.

4. An electrical distributor comprising a rotating part and a stationarypart enclosing said rotating part, said rotating part having a core ofconducting material and an outer layer of insulating material arrangedfor sliding contact with said stationary part, said layer havingopenings therethrough registering iu certain positions of said rotatingpart with contacts on said stationary part, and a liquid conductingmedium in said openings in contact with said core for cooperation withthe. contacts on said stationary part.

5. An electrical distributor comprisinf.r a rotating part and astationary part enc 0s- .ing said rotating part, said rotating parthaving a core of conducting material and an outer layer of insulatingmaterial arranged for sliding` contact with said stationary part, saidlayer having openings spaced longitudinally and circumferentiallythereof, said openings registering in certain positions of said rotatingpart with contacts on said stationary part, and a liquid conductingmedium in said openings in contact with said core for cooperation withthe contacts on said stationary part.

6. rin electrical distributor comprising a stationary part, a rotatablepart within said stationary part and having an outer face in sliding'Contact with a complemental face on said stationary part, means in saidparts for successively closing an electric circuit comprising spacedcontact members on said parts. said members on one of said parts beingspaced circumferentially as well as longitudinally.

7. An'electrical distributor comprising a stationary part, a rotatablepart within said stationary part and having an outer face in slidingcontact with a complemental face on said stationary part` means in saidparts for'succcssively closing an electric circuit comprising spacedcontact members in the form of electrical conducting Huid trapped inopenings in the opposed faces of said parts and adapted to be inregistration in certain positions of said parts.

8. An electrical distributor I stationary part, a rotatable part withinsaid stationary part and having an outer face in sliding contact with acomplemental face on said stationary part, means in said parts forsuccessively closing an electric circuit comprising spaced contactmembers in the form of electrical conducting fluid trapped in openingsin the opposed faces of said parts and adapted to be in registration incertain positions of said parts, said members on one of said parts beingspaced circumferentially7 as well as longitudinally thereof.

9. Anv electrical distributor having relacomprising a tively movableparts in contact with each other, said parts having recesses adapted tobe brought into registration, and mercury in said recesses formingelectrical contacts.

l0. LAn electrical distributor having relatively movable parts incontact `with each. other, circuit ciosing members on said partsarranged to register in certain positions oi" said parts, the circuitclosing members on one part comprising mercuryv trapped in recesses insaid part.

ll. An electrical distributor comprising a stationary part, a rotatablepart Within said stationary part and havingan outer fac'- in slidingcontact With a complemental face on said stationary part, means in saidparts 'for successively closing an electric circuit comprising spacedcontact members in the i'orm of mercury trapped in openings in opposedfaces of said parts and. adapted to be in registration in certainpositions ot said parts.

12. An electrical distributor having` a cylindrical rotatable part, astationary part 'forming a closely tting housing ttor said rotatablepart, said stationznnT part having; openings therein, the outer ends otsaid openings beingi closed by `coanector ter-f minals and the innerends by said rotatable part, and electrical conducting fluid illing saidopenings to form inwardly disposed contact members.

13. An electrical distributor having a cylindrical rotatable part, astationary part, forming a closely fitting housing for said rotatablepart. said stationary part having openings therein. the outer ends ofsaid openings being closed by connector terminals and the inner ends bysaid rotatable part and mercury filling said openings to torni inwardlydisposed contact members.

la. An electrical switch comprising a nonconducting member arranged forsliding contact with a second non-conducting member, said members havingopposed recesses arranged to register in a certain position of saidparts, and electrical conducting fluid in s recesses for closing acircuit when said recesses are in registration.

l5. in electrical switch comprising a non-conducting member arranged forsliding contact with a second non-conducting member, said members havingopposed recesses therein arranged to register in a certain position ofsaid parts, and mercury in said recesses 'tor closing a circuit whensaid recesses are in registration.

Signed by me at Massachusetts this 15th day of April, 1922.

ILLIAM B. STEARNS.

